Re: [PATCH 1/1] powerpc/pseries/iommu: Fix window size for direct mapping with pmem

2021-04-19 Thread Leonardo Bras
On Tue, 2021-04-20 at 15:18 +1000, Alexey Kardashevskiy wrote: > > On 20/04/2021 14:54, Leonardo Bras wrote: > > As of today, if the DDW is big enough to fit (1 << MAX_PHYSMEM_BITS) it's > > possible to use direct DMA mapping even with pmem region. > > > > But, if that happens, the window size (l

Re: [PATCH 1/1] powerpc/pseries/iommu: Fix window size for direct mapping with pmem

2021-04-19 Thread Alexey Kardashevskiy
On 20/04/2021 14:54, Leonardo Bras wrote: As of today, if the DDW is big enough to fit (1 << MAX_PHYSMEM_BITS) it's possible to use direct DMA mapping even with pmem region. But, if that happens, the window size (len) is set to (MAX_PHYSMEM_BITS - page_shift) instead of MAX_PHYSMEM_BITS, caus

[PATCH 1/1] powerpc/pseries/iommu: Fix window size for direct mapping with pmem

2021-04-19 Thread Leonardo Bras
As of today, if the DDW is big enough to fit (1 << MAX_PHYSMEM_BITS) it's possible to use direct DMA mapping even with pmem region. But, if that happens, the window size (len) is set to (MAX_PHYSMEM_BITS - page_shift) instead of MAX_PHYSMEM_BITS, causing a pagesize times smaller DDW to be created,